End view of an updraft common-brick kiln with permanent side and end walls. Bordentown Brick Company, Bordentown. View of the top of same type of kiln, the uneven surface of the brick platting representing the s tling that has occurred during burning. anthracite in part. With coal, the fuel is sometimes placed on grate bars, or on the floor of the hearth. Continuous kilns.-These were originally designed to utilize the waste heat from burning. Many types have appeared, some of which are patented, but the principle of all is the same. It consists essentially in having a series of chambers, arranged in a line, circle or oval, and connected with each other and also with a central stack by means of flues. Each chamber holds about 22,000 bricks. In starting the kiln, a chamber full of bricks is first fired by means of exterior fire boxes, and while the water-smoke or steam is passing off, the vapors are conducted to the stack, but as soon as this ceases the heat from the chamber first fired is conducted through several other chambers ahead of it, before it finally passes to the stack. In this manner the waste heat from any chamber is used to heat the others. When any one compartment becomes red hot, fuel in the form of coal slack is added through small openings in the roof, which are kept covered by iron caps. As soon as one chamber has reached its maximum temperature, the next two or three ahead of it are being heated up while those behind it are cooling down. A wave of maximum temperature is therefore continually passing around the kiln. It is thus possible to be burning brick in certain chambers, filling others, and emptying still others, all at the same time, making the process a continuous one. Continuous kilns are employed in many States for burning common brick, and with considerable success, but only three are in use in New Jersey, and none of these are employed in burning building brick. 16 CL G |